Oil and gas servicing operations require fluid for a variety of reasons, most commonly during drilling and completions operations. The fluid may be used in drilling operations for lubricating the borehole, cleaning away cuttings, and maintaining control of the well by overcoming the reservoir pressure. In completion operations, fluid is generally used for stimulating the formation, such as by acidizing or fracturing, cleaning the well bore, and maintaining well control. In most cases the amount of fluid required is large and the fluid must be prepared and stored onsite during the operation. Onsite tanks may also be used to store fluids such as run-off water, diesel fuel, glycol, oils, waste products and the like. Upon completion of the drilling and completion operations however large volume tanks used to contain such fluids onsite may no longer be required.
In completion operations, the fluid used is a fracturing fluid which is typically a mixture of at least water and a proppant, such as sand. Tanks used to store the fracturing fluid, commonly referred to as frac tanks, are fluidly connected to a pump, such as by a hose or pipe, so as flow the fracturing fluid down the wellbore at sufficiently high pressures to fracture the formation. The proppant in the fracturing fluid enters the newly created void space and acts to prop the spaces open, permitting reservoir fluid to flow more freely to the wellbore.
One type of conventional frac tank is a rectangular shaped pre-assembled tank unit that is towed behind a truck as a tractor-trailer assembly. This type of conventional tank typically has a capacity of about 500 barrels. Thus, multiple tanks are needed onsite in situations where the fluid volume requirement is greater than 500 barrels, such as in completion operations for stimulating multiple zones in deep horizontal wells.
Another type of conventional frac tank consists of an assembly of multiple panels which are transported onsite for assembly of the tank thereat. The panels for the conventional multi-panel tanks are typically made of steel and are very heavy. Due to weight restrictions and the like, several truck-trailer units may be required to deliver the panels to the site. Further, the steel panels require an onerous assembly process as a result of many fasteners required to hold the tank panels together.
In the case of the conventional multi-panel tanks, where the surface or ground on which the tank is to be assembled is angled or is uneven and undulating, alignment and assembly of the panels may be problematic.
Clearly, there is a need for high volume, transportable fluid storage tanks that are light weight and easy to assemble, such as for temporary use onsite in the oil and gas industry.